Apparatus for mixing the contents within containers

ABSTRACT

The described invention concerns apparatus for gently and continuously agitating the contents of one or more elongated containers such as sampling phials, which consists of a number of cylindrical rollers borne by a base structure and positively driven for rotation all in the same sense of direction on rotation axes which are parallel, the cylindrical axis of each roller being inclined to its rotation axis, so that a container placed in supporting contact with any two adjacent rollers is rotated and simultaneously rocked in two dimensions.

States Patent I Unite Jelley Oct. 9, 1973 APPARATUS FOR MIXING THE CONTENTS WITHIN CONTAINERS [75] Inventor: Frank Edward Charles Jelley,

Burgess Hill, England [73] Assignee: Denley-Tech Limited, Sussex,

England 22 Filed: Jan.7, 1972 211 App]. No.: 216,161

[30] Foreign Application Priority Data [56] References Cited 1,940,492 12/1933 Gale 259/81 R 2,525,663 10/1950 Frye 259/81 R FOREIGN PATENTS OR APPLICATIONS 412,621 7/1934 Great Britain 259/81 R Primary ExaminerRobert W. Jenkins Att0rneylmirie and Smiley [57] ABSTRACT The described invention concerns apparatus for gently and continuously agitating the contents of one or more elongated containers such as sampling phials, which consists of a number of cylindrical rollers borne by a base structure and positively driven for rotation all in the same sense of direction on rotation axes which are parallel, the cylindrical axis of each roller being inclined to its rotation axis, so that a container placed in supporting contact with any two adjacent rollers is rotated and simultaneously rocked in two di- UNITED STATES PATENTS 520,205 5/1894 Heyligenstaedt 259/81 R 4 Claims, 2 Drawing Figures l r i I L- 7 RA 1* Q I a L l (1 RA I J 2 l i ll ,I I l i? RA l 41 t r I l Q l i Jan;

APPARATUS FOR MIXING THE CONTENTS WITHIN CONTAINERS BACKGROUND OF THE INVENTION This invention relates to mixer apparatus and in particular to apparatus for mixing or tumbling the contents of sealed or closed containers which are of circular (or approximately circular) cross section by rotating the containers and contents therein.

Such apparatus is well-known and comprises a plurality of parallel, closely-spaced, rotatable rollers arranged in a horizontal plane and suitably geared together so that they rotate in synchronism and in the same sense of rotational direction when driven by a motor or other driving means. A cylindrical container, or a container provided with two or more cylindrical bands, when placed between and supported by a pair of such rollers is caused to rotate when the rollers rotate, thereby tumbling the contents thereof. In such prior art it has been suggested to use two rollers rotat' ing eccentrically and such as to support a heavy drum or like container, the rollers being frictionally interconnected so as to rotate more or less synchronously; but in such suggestion the eccentricity of the rollers was to be such that they were not parallel.

Samples of blood in sealed containers for pathological or other examination may conveniently be remixed, to ensure homogeneity immediately prior to examination, by such apparatus, but it is believed that if a gentle rocking or see-saw motion is imparted to the sample containers during rotation, thorough mixing of the sam ple results whilst avoiding formation of froth or even breakdown of, or damage to, the blood cells such as may occur with mixers that have been proposed having a more violent mixing action.

It is desired that the apparatus be capable of thorough mixing of the contents of containers, but avoiding frothing of, or damage to, the contents, and that it be reliable in operation.

Previously, it has been suggested to agitate the contents of a drum of circular cross section by supporting it on four eccentric collars, two on a first shaft and two on a second parallel shaft (the shafts being interconnected by frictional means so as to rotate approximately synchronously); the eccentricity of the collars was such that, regarding them collectively as a rectangular support for the drum, they were eccentric oppositely on diagonals, so that the drum would not only be rotated but oscillated about two axes namely vertical and laterally transverse. One inevitable disadvantage of such arrangement, at least for comparatively delicate containers and sensitive liquids, is that very considerable slip necessarily occurs and this is a potentialsource of irregular motion and of vibration, not tolerable for purposes to which the present invention is directed.

SUMMARY OF THE INVENTION The present invention offers a very simple apparatus for the gentle agitation of such containers as glass specimen-tubes or phials used in'pathology or other kindred circumstances, by which a number of containers can simply be placed on the apparatus, which may well be continually running, and a number may be so placed virtually without regard to precise. size or proportions. When rotated and rocked, such frictional slip" as occurs is negligible.

According to the invention there is provided apparatus for agitating the fluid contents of one or a plurality of elongated containers comprising a plurality of cylindrical rotors which are rotated on parallel axes and positively interengaged for rotation in the same sense of direction and at the same speed on such axes, the rotors having their individual cylinder axes at an angle to the rotational axes and at all times parallel each to the other.

In a convenient arrangementwhich provides the required geometry, each roller is provided with a spindle extending from its ends and supported for rotation in journal or roller bearings and, at least at one end, having positive driving means such as a pinion. The extended spindles of a roller lie on the same axis and their axes are parallel; such axes are inclined identically, to the cylinder axes of the corresponding axes of the rollers, preferably the two ends of a roller are eccentric by an equal amount and at an angle of The axes of the spindles are preferably all in one plane which plane is horizontal.

The surfaces of the rollers may be of frictional material such as rubber and their-spindles are preferably geared together positively by gear trains in order to provide synthronism in rotation and to impart rotation to each roller in the same sense of direction.

It has been found that rotational speeds around 60 revolutions per minute affordad'equate mixing of blood samples, although differentspeeds may very well be necessary for different container contents. For example, a liquid of higher viscosity than blood may require a lower speed.

A mixer apparatus as herein described in which variable-speed driving means are provided is within the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a. plan view of a mixer apparatus with the gear-train and motor exposed, and

FIG. 2 is a side elevation of the apparatusof FIG. 1.-

DETAILED DESCRIPTION OF THE INVENTION hasa spindle 2A extending from each end, and each spindle 2A is borne by a nylon bearing 5 or 6.

In a roller 2, the spindles 2A lie onthe axis of rotation shown as RA in the drawings, but each spindle is eccentric with its associated roller end by an equal radial amount at each roller-end,-and'each spindle 2A is angularly displaced relatively to one, end of its roller by 180 relative to-that at the other end.T-hus, as seen in theside elevationof FIG. 2, the-cylindrical axis IJA of each roller 2 is inclined to the axis of rotation RA of each roller.

The spindles 2A ofthe roller ends adjacent to the bracket 4, extend rotatably through bearings 5 and each terminates in an identical gearwheel 7 fastened thereto by a transverse pin (not shown). Intermediate idler reversing gears 8, each freely rotating on a spindle fixed to bracket 4, mesh with gears 7 in such manner that if one roller 2 is rotated, all the others rotate in the same sense of direction and with the same speed of rotation, i.e., in synchronism.

Replacing one of the idler gears 8 is a driven gear 9 which meshes with adjacent gears 7 and thereby causes the rollers 2 to rotate when driven. Gear 9 is fastened to motor-shaft 10 of electric motor M which may be of the shaded-pole type suitably geared internally to provide an output shaft speed of 60 R.P.M. The motor M is fastened to baseplate l by means of fixing lugs or brackets (not shown).

A cover will normally be provided to enclose the motor and gears, but in the drawings this has been omitted for the purpose of clarity.

When the rollers 2 are driven to rotate by motor M, the plane in which the longitudinal axes LA all lie, oscillates two-dimensionally.

The spacing between bearings 5, and similarly between bearings 6 is greater than the diameter of a roller and so arranged that tubes C or other cylindrical container of compatible dimensions may be supported between any adjacent pair of rollers 2 merely having to be placed thereon.

In operation, the motion imparted to sample-tube C is rotary by virtue of the rotation of the rollers 2 with which it is frictionally engaged, and oscillatory in two dimensions by virtue of the geometry of the rollers and associated axles 2A.

I claim:

1. Apparatus for agitating the fluid contents of elongate, substantially cylindrical containers, comprising,

a base structure including a pair of spaced parallel supports,

a plurality of pairs of bearings respectively mounted on said supports, the bearings of each pair being co-axial with the axes of said pairs being parallel and substantially horizontally co-planar,

a plurality of rollers respectively rotatably supported by and between said pairs of bearings, and

means positively interconnecting and collectively driving said rollers rotatively on said bearing axes so that said rollers are driven uniformly,

said rollers each having a spindle on each end thereof respectively mounted in a pair of said bearings, said rollers being elongate of uniformly cylindrical configuration and extending substantially between the respective pairs of bearings, said spindles of each roller disposed coaxially and the spindle on at least one end being disposed eccentrically to the axis of that end, the rollers being disposed with said eccentric spindles at their corresponding ends and with their cylindrical axes parallel.

2. Apparatus according to claim 1 wherein the spindles on both ends of said rollers are eccentric to their respective ends.

3. Apparatus according to claim 2 wherein said spindles of each roller are oriented substantially apart.

4. Apparatus according to claim 1 comprising an array of at least three rollers. 

1. Apparatus for agitating the fluid contents of elongate, substantially cylindrical containers, comprising, a base structure including a pair of spaced parallel supports, a plurality of pairs of bearings respectively mounted on said supports, the bearings of each pair being co-axial with the axes of said pairs being parallel and substantially horizontally co-planar, a plurality of rollers respectively rotatably supported by and between said pairs of bearings, and means positively interconnecting and collectively driving said rollers rotatively on said bearing axes so that said rollers are driven uniformly, said rollers each having a spindle on each end thereof respectively mounted in a pair of said bearings, said rollers being elongate of uniformly cylindrical configuration and extending substantially between the respective pairs of bearings, said spindles of each roller disposed co-axially and the spindle on at least one end being disposed eccentrically to the axis of that end, the rollers being disposed with said eccentric spindles at their corresponding ends and with their cylindrical axes parallel.
 2. Apparatus according to claim 1 wherein the spindles on both ends of said rollers are eccentric to their respective ends.
 3. Apparatus according to claim 2 wherein said spindles of each roller are oriented substantially 180* apart.
 4. Apparatus according to claim 1 comprising an array of at least three rollers. 